1. Field of the Invention
The present invention relates to a reforming apparatus that generates hydrogen from fuel, and more particularly relates to a reforming apparatus that generates hydrogen from a fuel cell.
2. Description of the Related Art
In recent years, miniature electronic equipment such as a cellular phone, a notebook-size personal computer, a digital camera, a PDA (Personal Digital Assistance), and an electronic notebook has been remarkably progressed and developed. As the power source, primary batteries such as an alkali dry cell, a manganese dry cell and secondary batteries such as a nickel-cadmium battery, a nickel-hydrogen battery, a lithium-ion battery are used.
However, when the primary batteries and secondary batteries installed in the electronic equipment are verified in terms of effective use of energy, the effective use of energy is not necessary ensured. As described in, for example, Unexamined Japanese Patent Publication 2000-106201, study and development on the fuel cell that can achieve high energy use efficiency have now been actively conducted for the purpose of an alternative to the primary batteries and secondary batteries.
The fuel cell is one in which fuel is electrochemically reacted with oxygen in the air to directly extract electrical energy from chemical energy, and is placed as a promising battery with much future potential. Though hydrogen is cited as a fuel used in the fuel cell, there is a problem in treatment and storage since it is in a gaseous state at ordinary temperature. Accordingly, the use of a reformer that heats a liquid fuel such as alcohol and gasoline and steam at high temperature to generate hydrogen can be considered. In this-case, a system for storing the liquid fuel may be used since the size thereof is relatively small. In a case where the fuel cell of fuel reforming type is used as a power source of a miniature electronic equipment, not only the fuel cell but also a reformer must be miniaturized.
Generally, the reforming apparatus includes an evaporator, a reformer, and a carbon monoxide remover. The evaporator heats a liquid mixture of liquid fuel and water to evaporate the mixed solution. The reformer through which a pipe passes from the evaporator catalytically reacts a gaseous mixture evaporated by the evaporator by heat to generate hydrogen gas and carbon dioxide gas. The carbon monoxide remover through which a pipe passes from the reformer catalytically reacts carbon monoxide slightly contained in the gaseous mixture sent from via the pipe from the reformer by heat to remove the carbon monoxide from the gaseous mixture. The hydrogen gas of the gaseous mixture containing the hydrogen gas and carbon dioxide gas generated by the reforming apparatus is supplied to the fuel cell from the reforming apparatus to generate electric energy by the fuel cell.
By the way, it is desirable that all heat energy of the evaporator, reformer, and carbon monoxide remover be used in the reaction between water and liquid fuel. However, the heat energy will be partially released outside. Each of the evaporator, reformer, and carbon monoxide remover must be heat-insulated in order to effectively use the heat energy. However, this increases the entire size of the reforming apparatus by a heat insulating structure for heat-insulating the evaporator, reformer, and carbon monoxide remover.
Accordingly, an object of the present invention is to provide a small size reforming apparatus capable of efficiently using heat energy in reaction in multiple reactors such as an evaporator, a reformer, and a carbon monoxide remover.